#############################################################

import sys
sys.setrecursionlimit(10**7)

from heapq import heappop,heappush
from collections import deque,defaultdict,Counter
from bisect import bisect_left, bisect_right
from itertools import product,combinations,permutations
from math import sin,cos
#from math import isqrt #DO NOT USE PyPy

ipt = sys.stdin.readline
iin = lambda :int(ipt())
lmin = lambda :list(map(int,ipt().split()))

def make_divisors(n):
    lower_divisors , upper_divisors = [], []
    i = 1
    while i*i <= n:
        if n % i == 0:
            lower_divisors.append(i)
            if i != n // i:
                upper_divisors.append(n//i)
        i += 1
    return lower_divisors + upper_divisors[::-1]

#############################################################

N,K = lmin()
A = lmin()

ans = 0
for i in range(N):
    D = make_divisors(A[i])
    for d in D:
        cnt = 0
        for j in range(N):
            if i == j:
                continue
            cnt += min(A[j]%d,(-A[j])%d)
        if cnt <= K:
            ans = max(ans,d)

print(ans)